The most discomfiting thing in the Amnesty report is the story of Mamana Bibi, a 68-year-old grandmother killed by Hellfire missiles while tending her garden on Oct. 24, 2012:

“She was standing in our family fields gathering okra to cook that evening,” recalled Zubair Rehman, one of Mamana Bibi’s grandsons, who was about 119 ft away also working in the fields at the time. Mamana Bibi’s three granddaughters: Nabeela (aged eight), Asma (aged seven) and Naeema (aged five) were also in the field, around 115 and 92 ft away from their grandmother to the north and south respectively. Around 92 ft to the south, another of Mamana Bibi’s grandsons, 15-year-old Rehman Saeed, was walking home from school with his friend, Shahidullah, also aged 15.

Accustomed to seeing drones overhead, Mamana Bibi and her grandchildren continued their daily routine. “The drone planes were flying over our village all day and night, flying in pairs sometimes three together. We had grown used to them flying over our village all the time,” Zubair Rehman continued. “I was watering our animals and my brother was harvesting maize crop,” said Nabeela.

Then, before her family’s eyes, Mamana Bibi was blown into pieces by at least two Hellfire missiles fired concurrently from a U.S. drone aircraft.

Many residents of North Waziristan have begun taking sleeping pills as ‘the constant whine of drones overhead and fear of being killed made it impossible to fall asleep naturally.’

A second strike hit the field nearby a few minutes later, badly injuring one of Mamana Bibi’s grandsons who had run to the scene of the first explosion.

The report notes that “it is not possible for Amnesty International to fully assess the reasons behind the killing of Mamana Bibi without further information from the U.S. authorities,” though a Pakistani intelligence source suggested that a local Taliban fighter may have used a satellite phone nearby several minutes before the strike.

However, the nearest roads are almost 1,000 feet away from where she was hit. The strike came a year after now-CIA Director John Brennan claimed improbably that “there hasn’t been a single collateral death (in drone strikes) because of the exceptional proficiency, precision of the capabilities that we’ve been able to develop.”

The authors write that the “evidence indicates that Mamana Bibi was unlawfully killed,” according to international humanitarian law, and suggest that whoever is responsible be “brought to justice in fair trials.”

Other sections of the report detail the psychological effects of frequent drone strikes — and the frequent hovering of drones overhead — on the people who live below, noting that many residents of North Waziristan have begun taking sleeping pills as “the constant whine of drones overhead and fear of being killed made it impossible to fall asleep naturally.”

The reports come at a time when the administration is signaling its intention to shift away from the use of drones toward other counterterrorism tactics. However, as the report argues, President Obama’s few statements on the topic indicate that he favors a policy shift away from drones rather than legal guidelines on when and how they can be used.

The possibility that officials could be held responsible for incidents like the one that killed Mamana Bibi was always remote. It also seems inevitable that they will happen again.

Joshua Keating is a staff writer at Slate focusing on international affairs and writes the World blog. Follow him on Twitter.

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